Signal Processing

Signal processing elements are in the schemdraw.dsp.dsp module.

from schemdraw import dsp

Various Networks

with schemdraw.Drawing() as d:
    d += dsp.Line().length(d.unit/3).label('in')
    d += (inpt := dsp.Dot())
    d += dsp.Arrow().length(d.unit/3)
    d += (delay := dsp.Box(w=2, h=2).anchor('W').label('Delay\nT'))
    d += dsp.Arrow().right(d.unit/2).at(delay.E)
    d += (sm := dsp.SumSigma())
    d += dsp.Arrow().at(sm.E).length(d.unit/2)
    d += (intg := dsp.Box(w=2, h=2).anchor('W').label('$\int$'))
    d += dsp.Arrow().right(d.unit/2).at(intg.E).label('out', loc='right')
    d += dsp.Line().down(d.unit/2).at(inpt.center)
    d += dsp.Line().tox(sm.S)
    d += dsp.Arrow().toy(sm.S).label('+', loc='bot')

with schemdraw.Drawing() as d:
    d.config(fontsize=14)
    d += dsp.Line().length(d.unit/2).label('F(s)').dot()
    d.push()
    d += dsp.Line().up(d.unit/2)
    d += dsp.Arrow().right(d.unit/2)
    d += (h1 := dsp.Box(w=2, h=2).anchor('W').label('$H_1(s)$'))
    d.pop()
    d += dsp.Line().down(d.unit/2)
    d += dsp.Arrow().right(d.unit/2)
    d += (h2 := dsp.Box(w=2, h=2).anchor('W').label('$H_2(s)$'))
    d += (sm := dsp.SumSigma().right().at((h1.E[0] + d.unit/2, 0)).anchor('center'))
    d += dsp.Line().at(h1.E).tox(sm.N)
    d += dsp.Arrow().toy(sm.N)
    d += dsp.Line().at(h2.E).tox(sm.S)
    d += dsp.Arrow().toy(sm.S)
    d += dsp.Arrow().right(d.unit/3).at(sm.E).label('Y(s)', 'right')

Superheterodyne Receiver

Source.

with schemdraw.Drawing() as d:
    d.config(fontsize=12)
    d += dsp.Antenna()
    d += dsp.Line().right(d.unit/4)
    d += dsp.Filter(response='bp').fill('thistle').anchor('W').label('RF filter\n#1', 'bottom', ofst=.2)
    d += dsp.Line().length(d.unit/4)
    d += dsp.Amp().fill('lightblue').label('LNA')
    d += dsp.Line().length(d.unit/4)
    d += dsp.Filter(response='bp').anchor('W').fill('thistle').label('RF filter\n#2', 'bottom', ofst=.2)
    d += dsp.Line().length(d.unit/3)
    d += (mix := dsp.Mixer().fill('navajowhite').label('Mixer'))
    d += dsp.Line().at(mix.S).down(d.unit/3)
    d += dsp.Oscillator().right().anchor('N').fill('navajowhite').label('Local\nOscillator', 'right', ofst=.2)
    d += dsp.Line().at(mix.E).right(d.unit/3)
    d += dsp.Filter(response='bp').anchor('W').fill('thistle').label('IF filter', 'bottom', ofst=.2)
    d += dsp.Line().right(d.unit/4)
    d += dsp.Amp().fill('lightblue').label('IF\namplifier')
    d += dsp.Line().length(d.unit/4)
    d += dsp.Demod().anchor('W').fill('navajowhite').label('Demodulator', 'bottom', ofst=.2)
    d += dsp.Arrow().right(d.unit/3)

Direct Conversion Receiver

with schemdraw.Drawing() as d:
    d += dsp.Antenna()
    d += dsp.Arrow().right(d.unit/2).label('$f_{RF}$', 'bot')
    d += dsp.Amp().label('LNA')
    d += dsp.Line().right(d.unit/5).dot()
    d.push()
    d += dsp.Line().length(d.unit/4)
    d += (mix1 := dsp.Mixer().label('Mixer', ofst=0))
    d += dsp.Arrow().length(d.unit/2)
    d += (lpf1 := dsp.Filter(response='lp').label('LPF', 'bot', ofst=.2))
    d += dsp.Line().length(d.unit/6)
    d += (adc1 := dsp.Adc().label('ADC'))
    d += dsp.Arrow().length(d.unit/3)
    d += (dsp1 := dsp.Ic(pins=[dsp.IcPin(side='L'), dsp.IcPin(side='L'), dsp.IcPin(side='R')],
                        size=(2.75, 5), leadlen=0).anchor('inL2').label('DSP'))
    d += dsp.Arrow().at(dsp1.inR1).length(d.unit/3)
    d.pop()

    d += dsp.Line().toy(dsp1.inL1)
    d += dsp.Arrow().tox(mix1.W)
    d += (mix2 := dsp.Mixer().label('Mixer', ofst=0))
    d += dsp.Arrow().tox(lpf1.W)
    d += dsp.Filter(response='lp').label('LPF', 'bot', ofst=.2)
    d += dsp.Line().tox(adc1.W)
    d += dsp.Adc().label('ADC')
    d += dsp.Arrow().to(dsp1.inL1)

    d += dsp.Arrow().down(d.unit/6).reverse().at(mix1.S)
    d += dsp.Line().left(d.unit*1.25)
    d += dsp.Line().down(d.unit*.75)
    d += (flo := dsp.Dot().label('$f_{LO}$', 'left'))
    d.push()
    d += dsp.Line().down(d.unit/5)
    d += dsp.Oscillator().right().anchor('N').label('LO', 'left', ofst=.15)
    d.pop()
    d += dsp.Arrow().down(d.unit/4).reverse().at(mix2.S)
    d += (b1 := dsp.Square().right().label('90°').anchor('N'))
    d += dsp.Arrow().left(d.unit/4).reverse().at(b1.W)
    d += dsp.Line().toy(flo.center)
    d += dsp.Line().tox(flo.center)

Digital Filter

with schemdraw.Drawing() as d:
    d.config(unit=1, fontsize=14)
    d += dsp.Line().length(d.unit*2).label('x[n]', 'left').dot()

    d.push()
    d += dsp.Line().right()
    d += dsp.Amp().label('$b_0$', 'bottom')
    d += dsp.Arrow()
    d += (s0 := dsp.Sum().anchor('W'))
    d.pop()

    d += dsp.Arrow().down()
    d += (z1 := dsp.Square(label='$z^{-1}$'))
    d += dsp.Line().length(d.unit/2).dot()

    d.push()
    d += dsp.Line().right()
    d += dsp.Amp().label('$b_1$', 'bottom')
    d += dsp.Arrow()
    d += (s1 := dsp.Sum().anchor('W'))
    d.pop()

    d += dsp.Arrow().down(d.unit*.75)
    d += dsp.Square().label('$z^{-1}$')
    d += dsp.Line().length(d.unit*.75)
    d += dsp.Line().right()
    d += dsp.Amp().label('$b_2$', 'bottom')
    d += dsp.Arrow()
    d += (s2 := dsp.Sum().anchor('W'))

    d += dsp.Arrow().at(s2.N).toy(s1.S)
    d += dsp.Arrow().at(s1.N).toy(s0.S)

    d += dsp.Line().right(d.unit*2.75).at(s0.E).dot()
    d += dsp.Arrow().right().label('y[n]', 'right').hold()
    d += dsp.Arrow().down()
    d += dsp.Square().label('$z^{-1}$')
    d += dsp.Line().length(d.unit/2).dot()
    d.push()
    d += dsp.Line().left()
    d += (a1 := dsp.Amp().label('$-a_1$', 'bottom'))
    d += dsp.Arrow().at(a1.out).tox(s1.E)
    d.pop()

    d += dsp.Arrow().down(d.unit*.75)
    d += dsp.Square().label('$z^{-1}$')
    d += dsp.Line().length(d.unit*.75)
    d += dsp.Line().left()
    d += (a2 := dsp.Amp().label('$-a_2$', 'bottom'))
    d += dsp.Arrow().at(a2.out).tox(s2.E)